How can I select hundreds of items in the outliner that have similar names?
Try Select > Pattern. This will allow you to select objects based on a pattern with a set of wildcards.



The available wildcards are *, ?, and [...]


Use * to match any number of characters
Use ? to match a single character
Use [abc] (or [ABC], but this only matters if Case Sensitive is enabled) to match any letter, and [0123456789] to match any number between 0 and 9. You can match specific numbers too, e.g. [127] will only match 1, 2, and 7.


If you want to select all AsteroidA_LP... objects, then it sounds like you want something like AsteroidA_LP.*.